Diagnosis
Several specific diagnostic criteria can be used to diagnose vascular dementia, including the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria, the International Classification of Diseases, Tenth Edition (ICD-10) criteria, the National Institute of Neurological Disorders and Stroke- Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria, the Alzheimer's Disease Diagnostic and Treatment Center criteria, and the Hachinski ischemic score.
Lateralizing signs such as hemiparesis, bradykinesia, hyperreflexia, extensor plantar reflexes, ataxia, pseudobulbar palsy, and gait and swallowing difficulties may be observed.
Signs may include cognitive decline from a previously higher level of functioning; impairment of memory and two or more other cognitive areas; sufficient severity as to interfere with activities of daily living; cerebrovascular disease is present, defined by the presence of focal neurologic signs (e.g., hemiparesis, sensory deficit, hemianopsia, Babinski sign, etc.); evidence of relevant features consistent with cerebrovascular disease on brain imaging (CT or MRI).
In terms of cognitive testing patients have patchy deficits. They tend to have better free recall and fewer recall intrusions compared with patients with Alzheimer's disease. As small vessel disease often affects the frontal lobes, apathy early in the disease is more suggestive of vascular dementia because it usually occurs in the later stages of Alzheimer's. Consequently patients with vascular dementia perform worse than their Alzheimer's disease counterparts in frontal lobe tasks such as verbal fluency. They also tend to exhibit more perseverative behavior. They may also present with general slowing of processing ability, difficulty shifting sets and impairment in abstract thinking. In the more severe patients, or those patients affected by strategic infarcts in the Wernicke or Broca areas, dysarthrias and aphasias may be present.
The recommended investigations for cognitive impairment should be carried out, including a dementia screening blood test, chest X-Ray, CAT scan and ECG. The screening blood test should typically include full blood count, liver function tests, thyroid function tests, lipid profile, erythrocyte sedimentation rate, C reactive protein, syphilis serology, calcium serum level, fasting glucose, urea and electrolytes, vitamin B-12, folate. In selected patients HIV serology and autoantibody testing may be done.
Gross examination of the brain may reveal noticeable lesions and artery damage. Accumulation of various substances such as lipid deposits and clotted blood appear on microscopic views. The white matter is most affected, with noticeable atrophy and tissue loss, in addition to calcification of the arteries. Microinfarcts may also be present in the gray matter (cerebral cortex), sometimes in large numbers. On rare occasion, infarcts in the hippocampus or thamalus are the cause of dementia.
Read more about this topic: Multi-infarct Dementia